Hydroponics & The Nutrient Film Technique (NFT)
Hydroponics & The Nutrient Film Technique (NFT)
The term hydroponics refers to a system of growing plants that does not rely on soil. There are six main types of growing systems to choose from with hydroponics. This article focuses on the hydroponics growing method known as nutrient film technique or NFT. This information will help you decide if NFT hydroponics is right for you.
What is the Nutrient Film Technique?
This technique is the most widely used method by commercial growers. In these systems, the roots are suspended in a channel, while a shallow stream of water containing a solution of essential nutrients is recirculated through the bottom of the channel. The reason why it’s the most widely used among commercial growers is because it produces very high yields with a minimal footprint.
Understanding the Nutrient Film Technique
In NFT systems, four primary components are used:
- the channel, or grow tray, which contains the plants
- the reservoir, which contains the water and nutrient solution
- a submersible pump which pumps the water from the reservoir to the channel
- a drain tube which allows the water to flow back into the reservoir after being pumped up to the channel
With these systems, the reservoir also often use an aerator and air stones to keep the water and nutrients oxygenated.
You will need to place your grow tray at an angle to allow water to flow downward and reach the drain tube so that the water and any remaining nutrient solution can flow back to the reservoir.
In an NFT system, the roots of a plant hang down towards the channel bottom. This is important because it allows the roots to connect with the nutrient solution’s shallow film and absorb the nutrients they need to continue growing in a healthy manner. Another benefit of NFT is that the growing plants receive the water they need without becoming over-saturated. Each plant’s upper roots remain dry when using this method and receive the oxygen they need for sustained growth.
To summarize, here are the benefits you can expect when using NFT:
- Easy to disinfect hardware
- Easy to inspect roots
- Low consumption of water and nutrients
- Reduced risk of contaminating local groundwater makes this an environmentally friendly planting option.
- Roots of plants keep a stable conductivity and pH balance due to regular feeding and flushing that prevents the build-up of localized salt.
Green, leafy, and lightweight plants that have short root systems grow well using this planting technique. Typical examples include
- bok-choi
- broccoli
- cauliflower
- lettuce
- certain types of herbs
You should not use NFT to grow any plant larger than cabbage or heavy plants with larger root systems.
Solariver Solar Pond Aerator Designed for Use with NFT
Our company offers a Solar Pond Aerator product that comes complete with five air stones, a 10-watt solar panel, a DC air pump, and five 10-foot lengths of quarter-inch flexible plastic tubing. The dimensions of each piece of equipment are as follows:
- Air stones: 1.2 inches
- Maximum air flow: 0.35 CFM
- Maximum air pressure: 9.67 PSI
- Solar panel dimensions: 15.7 inches by 10 inches by .90 inch
- Solar pump dimensions: 9.25 inches by 6 inches by 3.25 inches
The Solar Powered Pond Aerator is affordable at $170, simple to use, and provides several environmental benefits. With this tool, you can keep your pools, ponds, and NFT hydroponic systems continually aerated. You will find the Solar Pond Aerator easy to maintain once you have set it up, and it does not generate an electric bill. Other benefits you can expect when using this high-quality Solariver product include:
- Breakdown and eliminate the presence of bacteria.
- Eliminate unpleasant odors that can come from standing bodies of water by adding oxygen and helping the water to circulate better.
- Help to reduce the mosquito population.
- Reduce the growth of algae in your ponds and pools.
The staff at Solariver is happy to answer any additional questions you have about this or other products. We offer free shipping on all orders over $100 in the Continental US.
Feel free to reach out to us today, contact us.
Other Types of Hydroponic Gardening Systems
Here’s a brief overview of the other types of hydroponic gardening systems.
Non-NFT Types of Hydroponics
Aeroponics. This method is highly effective, but it is also one of the costliest methods of hydroponic gardening. With aeroponics, roots and plants remain suspended in the air. Mist from the reservoirs spray continuously over the plants and their roots. You also have the option to spray mist onto the plants and roots using a timed cycle with just a few minutes between each spray.
Some benefits of aeroponics include greater oxygen exposure for roots, a reduced risk of under-saturation or over-saturation, and it is easy to monitor and maintain. Drawback to consider include the higher cost and how much of an impact a broken nozzle or mist system can have on the plants.
Deep water culture (DWC) systems use a floating raft to hold plants over a solution tank. This type of system does not use any water pumps. The DWC method of hydroponics is inexpensive and simple to maintain.
Drip Systems are most appropriate in a commercial setting because they are most effective with large-scale operations. This system is similar to NFT typically used on private property. The plants remain in a separate channel suspended over a thin layer of nutrient solution and water while sitting in net pots. An attached pump moves water through the channel to improve the uptake of nutrients and oxygen. The leftover nutrient solution then flows back towards the reservoir for later reuse.
Using a drip system gives growers greater control over the plant feeding schedule. Growers must have advanced knowledge of nutrient and pH levels and monitor them frequently. Unlike most other types of hydroponic gardening systems, drip systems do not recirculate all leftover nutrient solution. Unfortunately, this can cause a high level of waste.
Ebb and flow also known as flood and drain. This system floods plants with nutrients on a timed cycle. It’s not quite as flexible as some of the other systems. However, growers who prefer this system appreciate the fact that it does not expose the roots of their plants to nutrient solution on a continuous basis.
You need to place plants in a tray as a growing medium to start using ebb and flow. A timed pump then floods the plants with nutrients according to the schedule you set. Some factors that impact flooding cycles include air temperature, growth cycle, and plant types. Unused nutrient solution flows back to the reservoir for later reuse.
The yield and growth you receive from using the ebb and flow system can be promising if you monitor your plants often. On the downside, plants may become dry or over-saturated without frequent monitoring.
Wicking is the simplest type of hydroponics. Water and nutrients transport to the root of each plant using a wick made from a piece of felt or rope. You will need to suspend your plants in a growing medium like perlite or coconut. One end of the wick sits in the growing solution and the other lies in the plant’s growing media. The benefit of this approach is that it allows the wick to transport nutrients and water to plants at a rate that meets their growth requirements.
Growers consider wicking a passive type of hydroponics because using it does not require water pumps or air pumps. This is also the lowest cost option of all six types of hydroponics.
